On Formation of Fayalite by Fe3O4-SiO2 Solid Phase Reaction during a Sintering Process

Dried sludge as additive for making ceramsite is a new effective approach for disposal of sludge. In this study sewage sludge, water glass and clay were chosen as the components, the optimal ratio of the components and the most appropriate conditions were obtained. The functions of primary components in the sintering process, porosity formation mechanism and solid phase reaction also have been discussed. The optimized process parameters were shown as follows: the ratio of dried sludge /clay (wt%) was 33%, ratio of adherent /clay (wt%) was 15%, sintering temperature was 1000 °C, sintering time was 10 min. Bulk density was 582 kg m−3, particle density was 1,033 kg m−3, water absorption was 9.5%, porosity was 43.7%. SEM, EDS, XRD and XRF analyses were also carried out. The results indicate that dried sludge as raw material is a good way for making ceramsite. Biological Aerated Filters (BAFs) with filter media of Guangzhou ceramsite, Jiangxi ceramsite, activated carbon and ceramsite (obtained in test) were selected to treat municipal wastewater. The average removal efficiencies of ceramsite (obtained in test) for turbidity, COD, SCOD and NH3-N were about 96.4%, 76.2%, 59.6% and 82.3% respectively and were higher than those of other ceramsites.

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On Formation of Fayalite by Fe3O4-SiO2 Solid Phase Reaction during a Sintering Process

Tetsu-to-Hagané Overseas ◽

10.2355/isijintoverseas.3.1_13 ◽

1963 ◽

Vol 3 (1) ◽

pp. 13-20

Author(s):

Teruo Ikeno ◽

Yukiyoshi Itoh

Keyword(s):

Solid Phase ◽

Solid Phase Reaction ◽

Phase Reaction ◽

Sintering Process

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Preparation and Thermoelectric Properties of Bi Doped Ca3Co4O9 Based Thermoelectric Materials

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.783.144 ◽

2018 ◽

Vol 783 ◽

pp. 144-147

Author(s):

Jing Wang ◽

Qin Chen ◽

Xia Chun Zhu ◽

Seok Je Lee ◽

Kyoung Woo Park ◽

...

Keyword(s):

Thermoelectric Properties ◽

Figure Of Merit ◽

Phonon Scattering ◽

Solid Phase ◽

Solid Phase Reaction ◽

Phase Reaction ◽

Sintering Process ◽

Spin Entropy ◽

Plasma Sintering ◽

Spark Plasma

Polycrystalline Ca3-xBixCo4O9 samples have been prepared by solid-phase reaction followed by spark plasma sintering process. The thermoelectric properties have been systematically investigated from room temperature to near 1000K. It is found that the change of the carrier concentration leads to the change of resistivity, which is mainly associated with doping induced point defect phonon scattering. The change of the thermal potential mainly comes from the spin entropy. In addition, polycrystalline Ca3-xBixCo4O9 had a maximum figure of merit of 0.30 at 973 K, which was about 50% higher than Ca3Co4O9. It indicated that doping approach can effectively improve the thermoelectric performance of Ca3Co4O9+δ-based material.

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Optimization of Degreasing-Sintering Process for Mg2Si/PLA Mixture and Influences of Additive Amount of Al on Sintered Density and Thermoelectric Performance of Mg2Si Fabricated by the Optimized Process

MRS Advances ◽

10.1557/adv.2020.87 ◽

2020 ◽

Vol 5 (10) ◽

pp. 459-467

Author(s):

Takashi Itoh ◽

Takumi Nakano

Keyword(s):

3D Printing ◽

Polymer Composite ◽

Sintered Density ◽

Solid Phase ◽

Fused Deposition Modelling ◽

Solid Phase Reaction ◽

Phase Reaction ◽

Sintering Process ◽

Fused Deposition ◽

Metal Polymer

ABSTRACTFused deposition modelling (FDM) type of 3D printing is widely used for manufacturing complex shaped polymer products. Recently, the metal/polymer composite products can be made by 3D printer using metal/polymer composite filament. Now, we are planning to develop a new manufacturing process of the thermoelectric (TE) elements or modules by combining the FDM-type 3D printing and the degreasing-sintering process. In this work, we focused on the degreasing-sintering process of the mixture of Mg2Si and polylactic acid (PLA) powders. Mg2Si compound powder was synthesized by a liquid-solid phase reaction (LSPR) method. The powder mixtures of Mg2Si, Al and PLA were pressed and heated in a pulse discharge sintering (PDS) chamber under a vacuum in various degreasing conditions. Following the degreasing, the sintering of Mg2Si was carried out in the same PDS chamber at various starting sintering temperatures. Sintered density, Seebeck coefficient and electrical resistivity of the consolidated Mg2Si were measured and the power factor as a TE performance was estimated from the TE properties. The optimum conditions of degreasing-sintering process maximizing the sintered density and the TE performance of Al-doped Mg2Si were investigated. Furthermore, the influences of the additive amount of Al on the sintered density and the TE performance of Mg2Si fabricated via the optimized degreasing-sintering process were investigated.

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Mechanism of the solid-phase reaction of magnesium with organic halides

Journal of Organometallic Chemistry ◽

10.1016/s0022-328x(00)98860-0 ◽

1983 ◽

Vol 243 (1) ◽

pp. 123-129 ◽

Cited By ~ 10

Author(s):

G Sergeev

Keyword(s):

Solid Phase ◽

Solid Phase Reaction ◽

Phase Reaction ◽

Organic Halides

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Fe3O4@C Nanoparticles Synthesized by In Situ Solid-Phase Method for Removal of Methylene Blue

Nanomaterials ◽

10.3390/nano11020330 ◽

2021 ◽

Vol 11 (2) ◽

pp. 330

Author(s):

Hengli Xiang ◽

Genkuan Ren ◽

Yanjun Zhong ◽

Dehua Xu ◽

Zhiye Zhang ◽

...

Keyword(s):

Methylene Blue ◽

Solid Phase ◽

Raw Materials ◽

Phase Method ◽

Maximum Adsorption Capacity ◽

High Catalytic Activity ◽

Solid Phase Reaction ◽

Phase Reaction ◽

High Concentrations

Fe3O4@C nanoparticles were prepared by an in situ, solid-phase reaction, without any precursor, using FeSO4, FeS2, and PVP K30 as raw materials. The nanoparticles were utilized to decolorize high concentrations methylene blue (MB). The results indicated that the maximum adsorption capacity of the Fe3O4@C nanoparticles was 18.52 mg/g, and that the adsorption process was exothermic. Additionally, by employing H2O2 as the initiator of a Fenton-like reaction, the removal efficiency of 100 mg/L MB reached ~99% with Fe3O4@C nanoparticles, while that of MB was only ~34% using pure Fe3O4 nanoparticles. The mechanism of H2O2 activated on the Fe3O4@C nanoparticles and the possible degradation pathways of MB are discussed. The Fe3O4@C nanoparticles retained high catalytic activity after five usage cycles. This work describes a facile method for producing Fe3O4@C nanoparticles with excellent catalytic reactivity, and therefore, represents a promising approach for the industrial production of Fe3O4@C nanoparticles for the treatment of high concentrations of dyes in wastewater.

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Microstructure and Mechanical Properties of ZrB2/h-BN Multiphase Ceramics by Low-Temperature Reactive Sintering

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.697.510 ◽

2016 ◽

Vol 697 ◽

pp. 510-514 ◽

Cited By ~ 1

Author(s):

Feng Rui Zhai ◽

Ke Shan ◽

Ruo Meng Xu ◽

Min Lu ◽

Zhong Zhou Yi ◽

...

Keyword(s):

Mechanical Properties ◽

Relative Density ◽

Fracture Strength ◽

Solid Phase ◽

Raw Materials ◽

Solid Phase Reaction ◽

Phase Reaction ◽

Microstructure And Mechanical Properties ◽

Multiphase Ceramics ◽

Strength And Toughness

In the present paper, the ZrB2/h-BN multiphase ceramics were fabricated by SPS (spark plasma sintering) technology at lower sintering temperature using h-BN, ZrO2, AlN and Si as raw materials and B2O3 as a sintering aid. The phase constitution and microstructure of specimens were analyzed by XRD and SEM. Moreover, the effects of different sintering pressures on the densification, microstructure and mechanical properties of ZrB2/h-BN multiphase ceramics were also systematically investigated. The results show that the ZrB2 was obtained through solid phase reaction at different sintering pressures, and increasing sintering pressure could accelerate the formation of ZrB2 phase. As the sintering pressure increasing, the fracture strength and toughness of the sintered samples had a similar increasing tendency as the relative density. The better comprehensive properties were obtained at given sintering pressure of 50MPa, and the relative density, fracture strength and toughness reached about 93.4%, 321MPa and 3.3MPa·m1/2, respectively. The SEM analysis shows that the h-BN grains were fine and uniform, and the effect of sintering pressure on grain size was inconspicuous. The distribution of grain is random cross array, and the fracture texture was more obvious with the increase of sintering pressure. The fracture mode of sintered samples remained intergranular fracture mechanism as sintering pressure changed, and the grain refinement, grain pullout and crack deflection helped to increase the mechanical properties.

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